The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Internal combustion engines draw air into an intake manifold through an air intake and a throttle. The air is mixed with fuel to create an air/fuel (A/F) mixture. The A/F mixture is combusted within cylinders to drive pistons that apply a torque to a crankshaft. For example, the torque applied to the crankshaft from the pistons due to combustion may be referred to as “engine torque.” The engine torque may cause the crankshaft to rotate. The rotational speed of the crankshaft may be referred to as “engine speed,” and may be measured in revolutions per minute, or RPM.
Engine torque is transferred from the crankshaft to one or more wheels of a vehicle via a transmission. For example, the transmission may be a manual transmission (i.e. operated by a driver) or an automatic transmission (i.e. operated by a control module). The transmission may further include a plurality of gears that translate the engine torque to wheel torque. In other words, each of the plurality of gears may translate the rotational speed of the engine crankshaft to a different rotational speed of the vehicle wheels. More specifically, gear ratios represent relationships between each of the plurality of gears and the crankshaft, respectively. For example only, a lowest gear (e.g. first gear) may include a gear ratio of 3.5:1 and a highest gear (e.g. fifth gear) may include a gear ratio of 0.7:1.
A shift operation between the plurality of gears of the transmission may be one of an up-shift (i.e. shifting to a higher gear) or a down-shift (i.e. shifting to a lower gear). The shift operation may further be defined as power-on (i.e. a shift operation when an accelerator pedal is depressed) or power-off (i.e. a shift-operation when an accelerator pedal is not depressed). Power-on shift operations (up-shifts and down-shifts) may require more precise control due to driver input during the shift operation (e.g. via an accelerator pedal).